This invention relates to an article storage facility and a control method for the storage facility. More particularly, the invention relates to an article storage facility and a control method for the storage facility, including an article storage structure with a plurality of storage units arranged in a horizontal direction and having a first storage structure end and a second storage structure end, an article support disposed on a side of the first storage structure end of the article storage structure for supporting articles to be stored or retrieved, a travel path extending in the horizontal direction and having a first path end located in association with the first storage structure end and a second path end located in association with the second storage structure end, a plurality of mobile bodies configured to travel along the travel path to transport articles between the article storage structure and the article support, each of the mobile bodies having an article transfer device, and a control device for controlling operation of the plurality of mobile bodies.
The above article storage facility causes the mobile bodies to perform article transporting operation for transporting articles between the storage units and article support. In a depositing operation an article on the article support is stored in one of the storage units of the article storage structure. In a delivering operation, an article in one of the storage units of the article storage structure is delivered to the article support.
Such an article storage facility aims at improved transport capacity by using a plurality of mobile bodies.
A conventional article storage facility includes two mobile bodies, article supports arranged adjacent opposite ends of an article storage structure longitudinally of a travel path, and a control device for controlling operation of the two mobile bodies. The control device causes one of the two mobile bodies to engage in an article transporting operation for transporting an article between one of the storage units and one of the article supports arranged adjacent the opposite ends of the article storage structure longitudinally of the travel path, and causes the other of the two mobile bodies to engage in an article transporting operation for transporting an article between one of the storage units and the other of the article supports arranged adjacent the opposite ends of the article storage structure longitudinally of the travel path (see Japanese Unexamined Patent Publication No. 2002-175117, for example).
This conventional article storage facility includes a common range formed in a middle portion of the article storage structure longitudinally of the travel path where any one of the two mobile bodies can enter but simultaneous entry of the two mobile bodies is restricted, and individual ranges formed at opposite sides of the common range longitudinally of the travel path, each individual range receiving only one of the two mobile bodies. The control device is constructed for controlling operation of the two mobile bodies such that admittance to the common range is restricted to one mobile body, and only one of the two mobile bodies is allowed to enter each individual range.
In the above conventional article storage facility, the two mobile bodies cannot enter the common range, and thus the two mobile bodies cannot transport articles simultaneously to storage units in the common range. Therefore, for transporting articles to the storage units in the common range, only the transport capacity of one mobile body is made available. There is a possibility that improvement in transport capacity cannot be realized.